ACTRESS-SINGER Sheryl Lee Ralph was a co-star in the original production of "Dreamgirls" on Broadway and alarmed about the health of some of her friends.

It was the 1980s and Ralph knew of male dancers who developed painful neuropathy that prevented them from performing. Others were marked with strange, purple lesions and later died from what was thought to be a "gay men's cancer." Back then, as researchers tried to figure out what was going on, the disease was marked by intense stigma and shame.

Ralph, who would go on to become known as the mother from the UPN sitcom "Moesha," wanted to do something to help, so she came up with the idea of hosting an annual benefit concert to raise money for AIDS research. Fast forward several decades later and Divas Simply Singing has become a highly anticipated - not to mention signature - event for the Tony Award-nominated actress.

This summer, for the first time, Ralph will stage the concert in Philadelphia, as well as in Los Angeles in October. For her first Philly show, she's expecting an all-star lineup at the Dell Music Center on Saturday night, including Faith Evans, Monifah, Angela Winbush, Kelly Price and Philly's own Carol Riddick.

She and I chatted about the show earlier this week, and got caught up to date on other things in this diva's life, including her son's recent graduation from Drexel University as well as her 10-year wedding anniversary with state Sen. Vincent Hughes, D.-Phila., which she celebrated last month. (Ralph and I both had our weddings on the same day, so that's something we always make small talk about.)

It turns out that, as part of the prenuptial agreement she made with Hughes, she'd agreed to eventually take his last name. So, now her legal name is Sheryl Lee Ralph-Hughes.

These days, Ralph, who co-stars on Showtime's "Ray Donavan" and TVLand's "Instant Mom," divides her time between Los Angeles and Philadelphia, flying back and forth every few weeks to be with Hughes.

This marks the 25th year Ralph has been doing Divas Simply Singing.

"Really what got me started was, as a young woman, seeing how awful people were to people in their time of need, people who were suffering and dying with AIDS," Ralph said. "And because of that, the little church girl in me said, 'We can do better than this.' And that's how I started Divas Simply Singing."

The early years were rough. Celebrities such as Ralph weren't exactly lining up to attach themselves to AIDS-related causes.

Ralph recalled, "They told me I was a fool. They told me it was a waste of my time. They told me I wasn't a big enough star to take on an issue like that. Oh, they said awful things. But I knew in my mind, it wasn't about the awful things that people would say about me. It was about the right thing to do."

What she's doing is as needed then as it is now. Ralph pointed out how this past spring, health officials announced that they'd seen a dramatic spike in HIV infections in rural Indiana.

Ralph estimates that she's raised about $2 million in the quarter century she has hosted the fundraiser.

"I'm so happy and so thrilled that, after all of these years, we are able to bring the show to Philadelphia and to have everybody so excited," she told me. "It has been great. It has been difficult. But it has been great. It's always hard to move something of this size. And to most people, they don't get it.

"They don't understand. They're like, 'Whoa, wait a minute. It's how many people?' . . . But when they see it, they will be, like, 'Oh, wow, now we get it.' It's something you've got to feel and you've got to experience."

From what I hear, this show is quite the treat for your ears - and also your eyes. I asked Ralph, who's always so glamorous, what she had planned for her own attire.

"I'll be wearing everything, and very big hair, because the bigger the hair, the closer to God," Ralph quipped, laughing. "That's part of the whole diva experience."

Tickets for Saturday's Divas Simply Singing are available through Ticketmaster or (Use the code "diva" for half-price tickets or to get two for the price of one.) Showtime is at 8 p.m. Address: Dell Music Center, 2400 Strawberry Mansion Drive.